二核Fe/S化合物(Et_4N)_2[Fe_2S_2Br_4]的合成与结构

Crystal Structure of Tetraethylammonium Di-μ2-sulfido-bis[dibromoiron( III) ]

标题化合物(Et_4N)_2[Fe_2S_2Br_4](1)在VS_4^(3-)/FeBr_2/imnt^(2-)/Et_4NCI的反应体系中获得,它属于单斜晶系,空间群P2_1/n,主要晶胞参数为:α=0.91193(2)nm,b=1.03874(3)nm,c=1.54360(1)nm,β=105.090(1)°,V=1.41177(5)nm^3,Z=2, ρ=1.778g/cm^3,μ=6.841cm^(-1),F(000)=748,结构精修结果为:R_1=0.0287,wR_2=0.0640.簇阴离子[Fe_2S_2Br_4]^(2-)含有一个菱形Fe_2S_2单元,铁的配位几何构型明显偏离了理想的T_d对称性,导致整个阴离子的对称性降低为D_(2h).同时观察到它的Fe-Br键呈现反常加长倾向.

The title complex (Et4N)2[Fe2S2Br4] was obtained from a reaction system of VS43- /FeBr2/ imnt2-/Et4NCl.It crystallizes in the monoclinic space group P21/n, with a =0.91193 (2), b =1.03874(3), c = 1.54360(1)nm, β= 105.090(1)°, V = 1.41177(5)nm3, Z = 2,Dc = 1.778g/cm3,F(000) = 748, R1 = 0.0287 and wR2 = 0.0640 for 1617 reflections with I > 2.0σ(I). The cluster anion [Fe2S2Br4]2- contains a rhombic Fe2S2 unit in which the geometry of the Fe sites deviates obviously from the idealized Td symmetry leading to a D2h symmetry for the cluster anion. Meanwhile, an irregular variation was observed for Fe-Br bond distances in the complex.